The Clan/Sept History

The many Irish surnames in use today have long rich histories behind them. The
name O Lonergan originally appeared in Gaelic as O Longargain.

Many variations of the name O Lonergan were found in archives from the Middle
Ages. These variations can be somewhat explained by the facts that the general
population was illiterate and therefore had little control over how their names
were documented. The spelling and language in which the people's names were
recorded was often up to the individual scribe. Variations of the name O
Lonergan found include Lonergan, Landergan, Landrigan, Ladrigan, Lonagan,
Landragan, Longargan and many more.
First found in county Tipperary, where they held a family seat from ancient
times.
The 18th and 19th centuries saw many Irish Families immigrate to North America
in search of land and opportunities. The largest influx of Irish immigrants to
the United States and British North America came during the 1840s when the Great
Potato Famine laid waste to their homeland. Hundreds of thousands left the
island in an attempt to escape the starvation and disease it brought. Although
the arrival of such a large number of destitute Irish was not welcomed by the
established population in the United States and what would become known as
Canada at the time, these Irish were an essential element to the rapid
development of these growing industrial nations. They filled the demand for the
cheap labor needed for the work in factories and in the construction of bridges,
roads, canals, and railways. An examination of passenger and immigration lists
has revealed many immigrants bearing the name of O Lonergan or one of its
variants: Edward Landragan settled in Philadelphia in 1858 along with John;
Thomas and Andrew Landragaon arrived in Philadelphia in 1876; Edmund and Michael
Lonergan arrived in Philadelphia in 1856..